Kenneth Branagh as Gilderoy Lockhart in the film adaptation of Harry Potter and the Chamber of Secrets. Photograph: Allstar/Cinetext/WARNER BROS

At A Celebration of Harry Potter at Universal Orlando Resort in Florida, JK Rowling spilled the beans about one of the most colourful characters from the Harry Potter books – Gilderoy Lockhart.

She revealed that the vain one-time defence against the dark arts teacher, who is played by Kenneth Branagh in the films, celebrates his birthday tomorrow, on 26 January, and she recorded three short audio clips for Pottermore.com – the digital platform for the Harry Potter stories and the world described within them - which we are exclusively showcasing here.

In the three clips, JK Rowling discusses her flamboyant creation's family background, a failed business idea and where the Sorting Hat nearly put him during his time at Hogwarts. The clips show her mischievous sense of humour, and a penchant for poking fun at the excesses of celebrity.